1885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/*********************************************************************** 2885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCopyright (c) 2006-2011, Skype Limited. All rights reserved. 3885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgRedistribution and use in source and binary forms, with or without 4885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgmodification, are permitted provided that the following conditions 5885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgare met: 6885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org- Redistributions of source code must retain the above copyright notice, 7885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgthis list of conditions and the following disclaimer. 8885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org- Redistributions in binary form must reproduce the above copyright 9885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgnotice, this list of conditions and the following disclaimer in the 10885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgdocumentation and/or other materials provided with the distribution. 11e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.org- Neither the name of Internet Society, IETF or IETF Trust, nor the 12885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgnames of specific contributors, may be used to endorse or promote 13885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgproducts derived from this software without specific prior written 14885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgpermission. 15e3ea049fcaee2247e45f0ce793d4313babb4ef69tlegrand@chromium.orgTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgAND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgIMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 19885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgLIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgSUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgINTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgCONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgPOSSIBILITY OF SUCH DAMAGE. 26885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org***********************************************************************/ 27885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 28885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#ifdef HAVE_CONFIG_H 29885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#include "config.h" 30885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#endif 31885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 32885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/* Approximate sigmoid function */ 33885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 34885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org#include "SigProc_FIX.h" 35885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 36885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/* fprintf(1, '%d, ', round(1024 * ([1 ./ (1 + exp(-(1:5))), 1] - 1 ./ (1 + exp(-(0:5)))))); */ 37885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgstatic const opus_int32 sigm_LUT_slope_Q10[ 6 ] = { 38885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 237, 153, 73, 30, 12, 7 39885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org}; 40885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/* fprintf(1, '%d, ', round(32767 * 1 ./ (1 + exp(-(0:5))))); */ 41885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgstatic const opus_int32 sigm_LUT_pos_Q15[ 6 ] = { 42885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 16384, 23955, 28861, 31213, 32178, 32548 43885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org}; 44885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org/* fprintf(1, '%d, ', round(32767 * 1 ./ (1 + exp((0:5))))); */ 45885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgstatic const opus_int32 sigm_LUT_neg_Q15[ 6 ] = { 46885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 16384, 8812, 3906, 1554, 589, 219 47885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org}; 48885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 49885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.orgopus_int silk_sigm_Q15( 50885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int in_Q5 /* I */ 51885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org) 52885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org{ 53885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org opus_int ind; 54885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 55885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( in_Q5 < 0 ) { 56885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Negative input */ 57885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org in_Q5 = -in_Q5; 58885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( in_Q5 >= 6 * 32 ) { 59885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org return 0; /* Clip */ 60885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 61885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Linear interpolation of look up table */ 62885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org ind = silk_RSHIFT( in_Q5, 5 ); 63885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org return( sigm_LUT_neg_Q15[ ind ] - silk_SMULBB( sigm_LUT_slope_Q10[ ind ], in_Q5 & 0x1F ) ); 64885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 65885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 66885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Positive input */ 67885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org if( in_Q5 >= 6 * 32 ) { 68885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org return 32767; /* clip */ 69885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } else { 70885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org /* Linear interpolation of look up table */ 71885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org ind = silk_RSHIFT( in_Q5, 5 ); 72885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org return( sigm_LUT_pos_Q15[ ind ] + silk_SMULBB( sigm_LUT_slope_Q10[ ind ], in_Q5 & 0x1F ) ); 73885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 74885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org } 75885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org} 76885f2ff5a7a7d6a73432d26a6c0ae9147e6b452sergeyu@chromium.org 77